The fine folks at Teradek have created VidiU, a device that enables you to stream video from your DSLR over Wi-fi. There is no computer needed at all. It attaches to your camera via the hotshoe, and it encodes video in the H.264 codec in real time. If you’re an Apple user, VidiU has an iOS app that will stream the video to your iDevice, so that you can the check your video stream’s quality. It is a bit pricey at $699, but if you find yourselves in situations where live video would be a boon, this is the device you should get. B&H has a product demo available, and you can purchase it here.